In recent years, there has been widespread use of a portable device (for example, a mobile telephone and a digital camera) capable of communication in accordance with a high-speed infrared communication protocol such as IrSS (registered trademark; hereinafter referred to as “IrSS”). Such a portable device can obtain image data and then directly transmit the image data, by a short-distance wireless telecommunication, to operation target devices, e.g., various household AV equipment such as a television and a HDD recorder. With this technology, a user can operate the portable device to, for example, cause (i) a HDD recorder to store image data or (ii) a television to display image data.
Further, a user can now cause instruction information for operating an operation target device to be included in an EXIF region of image data in, for example, a JPEG (Joint Photographic Experts Group) format. The user can thus use the above image data as operation data for operating operation target devices. With this technology, the user can use the operation device as a remote control for each operation target device by transmitting the operation data from the operation device, e.g., a portable device, to the operation target devices.
Suppose that, for example, a user has transmitted, from a portable device to a television, operation data which includes, in an EXIF region, instruction information, i.e., a set of (i) a URL (uniform resource locator) and (ii) an instruction to access a website specified by the URL. In this case, the television, upon receipt of the operation data, displays content such as the website specified by the URL, in accordance with the instruction information. This indicates that with the above technologies, (i) a user can, by transmitting operation data from a portable device to a television, easily cause the television to display desired content, and (ii) it is thus possible to provide an operation system which has a high operability and a high convenience.
A use case is assumed here in which only a user provided with a predetermined authority is permitted to view content within the operation system. In this case, it is common to require a user to enter information necessary for authentication, such as a user ID and a password, on a login screen or the like so that the user can achieve authentication as an authorized user.
Patent Literature 1, for example, discloses a system in which a user can use various services on a video recorder via a network by remotely operating the video recorder with a mobile telephone. The system can impose a restriction on the use of services by requiring the user to use the mobile telephone for user authentication. More specifically, after the user has successfully completed the authentication with use of the mobile telephone, the system supplies a user account to the mobile telephone. The user then registers the user account in the video recorder with use of a remote control for the video recorder. As a result, the user can use the services on the video recorder.
Further, Patent Literature 2 discloses a technique in which authentication for a terminal device is carried out in a server. Specifically, to allow a user to use, on a terminal device, a network service provided over a first communication network, the technique disclosed includes the steps of (i) transmitting security information from a server to a portable electronic device via a second communication network which is different from the first communication network, (ii) transmitting the security information by a short-distance wireless telecommunication from the portable electronic device to the terminal device in response to a request from the terminal device, and (iii) carrying out authentication in the server on the basis of the security information transmitted from the terminal device. Patent Literature 2 further discloses that by (i) transmitting identification information of a terminal device from the terminal device to the server and (ii) determining in the server whether the terminal device is permitted to use a service, security information is transmitted to only a terminal device which is permitted to use a network service. Patent Literature 2 further discloses that damage due to a security information leak is prevented by (i) generating new security information each time the terminal device becomes permitted to use a network service and (ii) transmitting such new security information to the portable electronic device.